Making Your Own PCBs
Ferric Chloride and the Art of Etching: A Photo Essay
1. Laser Printer
Select and old(er) Laser Printer. The newer one with toner management often don't transfer enough toner onto the paper.
2. Glossy Paper
I use old glossy magazine pages for this process. Some use photo paper and other types. Test some out to see what works.
3. Cut to Size
Note how I am not using the entire page but part of it taped to a normal A4 printer paper sheet, this is to avoid paper jams.
4. Clean the Copper Board
Clean the Copper Clad board. I often use some steel wool to give the surface light abrasion, the toner adheres better to this. Then clean with Isopropyl Alcohol.
4. Heat Transfer
Melt the toner onto the copper clad board by using either a laminator (this one is modified) or an iron. This process is tough to get right, so keep trying and experimenting until you have it. I feed the board with the paper on top through the laminator 10+ times.
5. Soak in Water
Soak the magazine paper off in water. Don't rush, just let it float off naturally and you'll be left with the toner on the copper. At this stage it's best to get an etch resistant pen and fill in any gaps or pitting.
7. Prepare to Etch
I use Ferric Chloride to etch. It's nasty stuff so make sure to follow the safety procedures and practices. Ventilation, eye, face and hand protection. Respect the process and try not to spill any -- it stains!
Place the board/s in Ferric Chloride bath and allow it to etch. It etches faster if you gently heat the Ferric Chloride and you gently agitate the solution being careful not to spill it. These boards took 40-50 minutes.
9. Water Bath
Place the etched board in a bath of water to stop the Ferric Chloride reaction and wash the boards. This should leave board with toner protecting the copper tracks.
10. Clean Off the Toner
Using Acetone to clean the toner from the copper tracks. This should take the black toner and leave the copper tracks below.
11. Examine the Result
At this stage, I use a magnifying glass to check the quality of the etch. I also use an multimeter to check the continuity of the copper tracks.
Use a 8mm drill bit to drill the holes in the board for any THT (Through Hole Technology) components (if you are making SMT boards you don't need to do this).
13. Cut the Boards
You can use tin snips, a saw, a sharp knife of various other methods to do this. Again, BE SAFE! Observer safety practices. I use a metal shear to make this process easy.
If you want your circuit board to last, it's a good idea to tin the board. If you look at an old analogue circuit you'll see they do this by building up a solder layer along the copper. You can also do this chemically but it's a dangerous and expensive process.
15. Populate & Solder
Once you have finished these steps, solder the components. Double checking your values at this stage can alleviate future problems.
This process is my method for creating PCBs and is just one of many methods for making PCBs. Nowadays it is often easier to get them professionally made by using an EDA Software such as Eagle, KiCAD or EasyEDA and upload the Gerber and Drill files for manufacture. The first few boards are generally cheap ($2 for 5 at the time of writing). However, there's something to be said for the process of hand-making your own boards and it's invaluable in testing your designs before you send them off to be made by JLPCB or similar companies.